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111.
Summary Capillary electrophoresis-amperometric detection is evaluated for simultaneous determination of rutin and forsythin. The cyclic voltammogram, hydrodynamic voltammogram, effect of pH, buffer concentration and SDS, and percent organic modifier on separation and detection were studied. Conditions were optimized as follows: 1.2 V detection potential; separation at 12 kV; 5 s at 15 kV for sample injection time and sample injection voltage; mobile phase 20 mM boric acid buffer; pH 8.4, containing 40 mM SDS and 10% (v/v) acetontrile. The method gave low detection limit as 0.001 mg mL−1 and 0.0005 mg mL−1 (S/N=3), wide linear range 0.005–0.5 mg mL−1 for rutin and forsythin, respectively. The relative standard deviations of peak current and migration time for 8 consecutive injections of the standard solution containing 0.1 mg mL−1 each compound were 4.78%, 3.63% and 6.40%, 2.95% for rutin and forsythin, respectively. In addition, levels of the two compounds in traditional Chinese herbal drugs were easily determined.  相似文献   
112.
Psychiatric and neurological disorders severely hamper patient’s quality of life. Despite their high unmet needs, the development of diagnostics and therapeutics has only made slow progress. This is due to limited evidence on the biological basis of these disorders in humans. Synapses are essential structural units of neurotransmission, and neuropsychiatric disorders are considered as “synapse diseases”. Thus, a translational approach with synaptic physiology is crucial to tackle these disorders. Among a variety of synapses, excitatory glutamatergic synapses play central roles in neuronal functions. The glutamate α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) is a principal component of glutamatergic neurotransmission; therefore, it is considered to be a promising translational target. Here, we review the limitations of current diagnostics and therapeutics of neuropsychiatric disorders and advocate the urgent need for the promotion of translational medicine based on the synaptic physiology of AMPAR. Furthermore, we introduce our recent translational approach to these disorders by targeting at AMPARs.  相似文献   
113.
More than 60% commonly used pharmaceutical active ingredients are chiral compounds. Developing more effective and safe chiral compounds has become a focus in the pharmaceutical industry. Chiral compounds widely exist in traditional Chinese medicine and include alkaloids, flavonoids, volatile oils, and amino acids. The characterization of chiral compounds used in traditional Chinese medicine remains limited. Here, the characterization of chiral compounds commonly used in traditional Chinese medicine is reviewed focusing upon their separation and pharmacology.  相似文献   
114.
通过对各种化学元素、化合物在人体中的作用与影响作出分析与总结,从现代科学的角度直观地解释了中医学中如阴虚、阳虚、正、邪、湿、热等的多个抽象概念和理论。为研究抽象而深奥难懂的中医学概念和理论提供了一个新的思路,使之转化为具体而直观的符合现代科学概念的理论。  相似文献   
115.
A speedy and selective ultra‐HPLC‐MS/MS method for simultaneous determination of deoxynivalenol (DON), 3‐acetyldeoxynivalenol (3‐ADON), 15‐ADON, nivalenol and fusarenon X in traditional Chinese medicines (TCMs) was developed. The method was based on one‐step sample cleanup using reliable homemade cleanup cartridges. A linear gradient mobile‐phase system, consisting of water containing 0.2% aqueous ammonia and acetonitrile/methanol (90:10, v/v) at a flow rate of 0.4 mL/min, and an Acquity UPLC HSS T3 column (100 mm×2.1 mm, 1.8 μm) were employed to obtain the best resolution of the target analytes. [13C15]–DON was used as the internal standard to accomplish as accurate as possible quantitation. The established method was further validated by determining the linearity (R2≥0.9990), sensitivity (LOQ, 0.29–0.99 μg/kg), recovery (88.5–119.5%) and precision (RSD≤15.8%). It was shown to be a suitable method for simultaneous determination of DON, 3‐ADON, 15‐ADON, nivalenol and fusarenon X in various TCM matrices. The utility and practical impact of the method was demonstrated using different TCM samples.  相似文献   
116.
采用活化酯法,将马兜铃酸A分别与牛血清蛋白(BSA)和卵清蛋白(OVA)偶联,得到免疫抗原马兜铃酸A-BSA和包被抗原马兜铃酸A-OVA.利用马兜铃酸A-BSA免疫Bal b/c小鼠,制得鼠单克隆抗体1A11,单抗效价为2×104;单抗为IgG1类,轻链为κ型;与其结构类似物马兜铃酸B、C和D的交叉反应率分别为2.8%,3.5%和31.2%.基于抗马兜铃酸A单克隆抗体的间接竞争酶联免疫分析方法(icELISA)的IC50为1.9 μg/L,检测范围为0.5~7.5 μg/L.icELISA添加回收率为86%~97%,相对标准偏差在5.2%~11.1%之间.利用所建立的icELISA测定了6个中药材和5个中成药中马兜铃酸A的含量,并用高效液相色谱法(HPLC)进行了验证,其中关木通、广防己、天仙藤、马兜铃和青木香中均检测出马兜铃酸A,而川木通和5个中成药中未检测到马兜铃酸A.结果表明: 本方法可用于中药中马兜铃酸A的快速检测.  相似文献   
117.
The paper reported a reliable analytical method for simultaneous determination of ochratoxin A (OTA) and ochratoxin B (OTB) in traditional Chinese medicines (TCMs) by ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS). The development of the method and investigations on the matrix influence were described in particular. The matrix effects were thereby minimized by using a reliable internal standard and a simple sample pretreatment. The established method was further validated by determining the linearity (R2 ≥ 0.9990), average recovery (86.3–114.2%), sensitivity (limit of quantitation 0.03–0.19 ng mL−1) and precision (relative standard deviation ≤ 13.1%). It was shown to be a suitable method for simultaneous determination of OTA and OTB in various TCMs. Finally, a total of 51 TCMs widely used in China were screened for OTA and OTB with the proposed method. The results showed that only 4 samples were contaminated with ochratoxins at low levels, indicating that it was low risk of ochratoxins to consumers who occasionally used TCMs.  相似文献   
118.
A strategy based on chemical markers’ fishing and knockout has been proposed for holistic activity and interaction evaluation of the bioactive components in herbal medicines (HMs). It was devised to screen bioactive-compound group that represents the efficacy of HM, estimate the bioactivity contribution of each component and elucidate the interactions of multi-components. This strategy was accomplished through the following steps: (1) screen out the chemical markers (target peaks) in a HM fingerprint using online two-dimensional turbulent flow chromatography/liquid chromatography–mass spectrometry technique, (2) fish target peaks and knockout any interested peak, and (3) evaluate the bioactivities of fishing and knockout portions. After comparison of the bioactivities of samples containing different target peaks, the efficacy of target-peak group, bioactivity contribution of each compound, and the interactions of multi-components are elucidated. Using Acetylcholinesterase (AChE) and Bulbs of Lycoris radiata (L. Herit.) Herb. (BLR) as the experimental materials, four target peaks were screened out as the AChE binders. By target peaks’ fishing and knockout, combined with activity evaluation, we observed that the bioactivity of the four-peak mixture is similar with the global bioactivity of BLR extract, and there are significant suppressive actions among these four target peaks. These results indicate that this proposed strategy is a useful approach for holistic screening of bioactive-compound group and elucidation of the multi-component interactions in HM.  相似文献   
119.
A simple method based on liquid chromatography coupled with diode array detection and electrospray ionization mass spectrometry (LC‐DAD‐ESI‐MS) was developed for the quality assessment of Cortex Phellodendri (CP), which was mainly derived from two species of Phellodendron chinense Schneid and Phellodendron amurense Rupr. Total 41 compounds, including 14 phenols, 24 alkaloids and three liminoidal triterpenes were identified or tentatively characterized from the 75% methanol extract of CP samples by online ESI‐MSn fragmentation and UV spectra analysis. Among them, two phenols and six alkaloids were simultaneously quantified using HPLC‐DAD method. The validated HPLC‐DAD method showed a good linearity, precision, repeatability and accuracy for the quantification of eight marker compounds. Furthermore, the plausible fragmentation pathway of the representative compounds were proposed in the present study. The differences of the chemical constituents content and the comprehensive HPLC profiles between the two CP species using LC‐DAD‐ESI‐MS method are reported for the first time, indicating that the CP drugs from different resources should be used separately in the clinic. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
120.
Ausgehend von der im ersten Teil begründeten Notwendigkeit, die mit der Szintillationskamera Impulsverteilung korrigieren zu müssen, wird in der vorliegenden Arbeit der Programmablanfplan für diese Korrekturrechnung mit Hilfe der elektronischen Datenverarbeitung (R 300) erläutert. Im gegenwärtigen Stadium der Entwicklung eines umfangreichen Konzepts zum Einsatz der EDV für die Szintigraphie – an der alle Nuklearmedizinischen Abteilungen der DDR beteiligt sind – erfolgt bei den Autoren die Ein- und ausgabe der Daten über Lochstreifen. Die Wirkung der Korrekturrechnung wird am homogenen Phantom selbst und an einer Pankreasunfersuchung demonstriert.  相似文献   
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